1. Field of Invention
This invention pertains to portable traffic barricades used to identify road hazards and give visual warning thereof to road and foot traffic. More particularly, the present invention relates to a portable barricade structure which is capable of surviving an impact without being destroyed or rendered non-reuseable.
2. Prior Art
Roads, highways, sidewalks and other areas of vehicular and foot traffic are frequently subject to maintenance and reconstruction activities. Typically, such maintenance interrupts the traffic pattern and requires a detour from normal traffic flow. Such unexpected changes in driving conditions result in greatly increased risk of accidents and concurrent damage to property and life. For example, 60% of all highway fatalities occur in construction work areas. Accordingly, federal and state laws require adequate delineation of such hazardous conditions.
The principal highway warning device in a construction zone is the traffic barricade. This device comprises a horizontal reflective member which has a large face or surface structure to provide immediate visual recognition during both daylight and nighttime hours. This horizontal member is typically supported by two pairs of legs which are attached to form a type of sawhorse configuration. In high risk areas, a blinking light is attached to the top of the barricade to get the attention of the passing traffic.
Originally, traffic delineators were constructed of wood. A horizontal board was mounted to vertically inclined boards in the referenced sawhorse configuration using nuts and bolts. Such barricades were very vulnerable to vehicle impact, which usually resulted in destruction of the barricades.
Because the wooden legs of the earlier barricades were subject to breakage, angle irons were substituted and attached to the horizontal cross-member using nuts and bolts. The greatly increased strength of the angle iron enabled the barricade to survive many low-speed impacts, but resulted in damage at higher speeds.
Because of these problems, attempts have been made to substitute fiber reinforced plastic legs in place of the angle iron. As with the angle iron, the cross-member and legs are bolted together to form a stiff, unitary structure. Although the fiber reinforced plastic legs were more capable of surviving impact, the cross panel and legs are still rigid and subject to breakage upon high speed impact of 30 miles per hour or more.
In an effort to provide a barricade capable of surviving impact by a vehicle, thermoplastic materials such as polyethelyne have been used to develop a single piece frame representing 1/2 of the sawhorse structure. These frames were then joined at the top to provide a stable stand. In addition to being very expensive, however, such thermoplastic barricades become brittle in cold weather and warp or sag in extreme heat. When sandbags or other heavy weights are draped over the barricade to stabilize them in winds, the thermoplastic material is often stretched and distorted out of shape.
Because of these and other adverse properties of plastic barricades, the conventional angle iron barricade has remained one of the principal warning devices at highway maintenance sites. This predominance continued despite the fact that the average life for the angle iron barricade is only about ninety (90) days. It is estimated each year that 1/2 million new barricade units are purchased to replace broken or damaged devices. Accordingly, one skilled in the art is very familiar with the extreme high cost of maintaining serviceable traffic barricades using angle iron legs, bolted to a wood or plastic cross-member as a single, rigid structure.